Why Your Furnace Has a Strange Smell
As the weather turns cold and you transition from cooling to heating your home, you may be worried about weird furnace smells in the air. Find out what the most common furnace smells mean and how proactive you should be about each one.
The Furnace Smells Musty
Musty furnace odors usually indicate mold growth somewhere in the HVAC system. To avoid exposing your family to allergy-inducing mold, tackle this problem right away.
A damp air filter can encourage mold, so wiping out the smell might be as straightforward as getting a new filter. If that doesn't help, the AC evaporator coil placed near the furnace could be the culprit. This component collects condensation, which could stimulate mold growth. You’ll need a professional’s help to inspect and clean the evaporator coil. When the problem still won't go away, start thinking about scheduling air duct cleaning. This service removes hidden mold, no matter where it's hiding in your ductwork.
The Furnace Smells Like Rotting Eggs
This is one of the most nerve-wracking furnace smells due to the fact that it most likely indicates a gas leak. The utility company adds a special substance called mercaptan to the natural gas supply to make leaks easier to notice.
If you detect a rotten egg smell close to your furnace or coming from your air ducts, shut down the heater immediately. If you know where the main gas supply valve is, shut that off too. Then, evacuate your home and contact 911, followed by your gas company. Don’t reenter the house until a professional confirms it’s safe.
The Furnace Has a Sour Stench
If you detect a sour smell that stings your nose while standing near the furnace, this could mean the heat exchanger is cracked. This vital component contains combustion fumes, like carbon monoxide, so a cracked heat exchanger could allow unsafe levels of CO gas into your home.
Carbon monoxide poisoning has the potential to be fatal, so shut off your furnace right away if you detect a sour odor. Then, contact an HVAC professional for an inspection. Consider replacing your furnace if a cracked heat exchanger is to blame. For your continued safety going forward, ensure you have functional CO detectors on every floor of your home.
The Furnace Smells Dusty
When you fire up the furnace for the first time after a while, you probably expect a dusty odor to show up for a little while. This is the smell of six months’ worth of dust burning away as the furnace wakes up. As long as the smell disperses within 24 hours, you shouldn't have anything to worry about.
The Furnace Has a Smoky Smell
Natural gas, oil and propane furnaces are combustion appliances, so they vent fumes up and out of your home. A smoky smell will sometimes mean the flue is backed up, and now fumes are settling back into your home. The odor can reach through the entire house, risking your family’s health if you neglect it. So shut down the furnace and contact a professional right away to schedule a repair.
The Furnace Smells Like Burning Plastic
Overheating and melted electrical components are the most likely reason for a burning plastic smell to make an appearance. A failing fan motor is another possibility. If you don’t tackle the problem, an electrical fire may start, or your furnace could suffer from irreparable damage. Turn off the heating system immediately and call an HVAC technician for help troubleshooting and repairing this weird furnace smell.
The Furnace Has an Oily Smell
If you have an oil furnace, you could notice this odor whenever the oil filter becomes clogged. Try replacing it to determine if that addresses the problem. If the smell persists for more than one day after carrying out this step, it might imply an oil leak. You’ll need help from an HVAC specialist to fix this problem.
The Furnace Reeks of Sewer Odors
Sewer gas smells very similar to spoiled eggs, so first determine the potential for a natural gas leak. If that’s not the source, your home's sewer lines could have an issue, like a dry trap or sewer leak. Try pouring water down your own drains, including the basement floor drain, to fill dried-up sewer traps. If the smell persists, you should contact a sewer line repair company.
Contact Service Experts Heating & Air Conditioning for Furnace Repair
If you're still uncertain, call an HVAC technician to assess and repair your furnace. At Service Experts Heating & Air Conditioning, we offer thorough diagnostic services to pinpoint the problem before we figure out the best solution. Then, we suggest the most viable, cost-effective repairs, alongside an up-front estimate for all options. Our ACE-certified technicians can resolve just about any heating malfunction, and we back our work with a 100% satisfaction guarantee for one year. For details about why your furnace smells bad or to request furnace repair near you, please contact your local Service Experts Heating & Air Conditioning office today.
